Traveling grates for incinerators



Dec. 6, 1966 F. s. SIMPSON 3,239,619

TRAVELING GRAIES FOR INCINERATORS Filed May 26, 1965 4 Sheets-Sheet l J amnion RANK 5. S/MPSOA/ Dec. 6, 1966 s. SIMPSON 3,289,619

TRAVELING GRATES FOR INCINERATORS Filed May 26, 1965 4 Sheets-Sheet :9,

FPA/VK 5. SIMPSON Dec. 6, 1966 F. s. SIMPSON 3,289,619

TRAVELING GRATES FOR INCINERATORS Filed May 26, 1965 4 Sheets-Sheet 5 1966 F. s. SIMPSON 3,289,619

TRAVELING GRATES FOR INCINERATORS Filed May 26, 1965 4 Sheets-Sheet 4 A. A am .1 .1

fimnzrfiou FPANK s. SIMPSON United States Patent 3,289,619 TRAVELING GRATES FOR INGINERATURS Frank S. Simpson, Alton, IllL, assignor to Illinois Stoker Company, Alton, 111., a corporation of Delaware Filed May 26, 1965, Ser. No. 453,926 11 (Ilaims. (Cl. 110-40) This application is a continuation-in-part of my ap plication Serial No. 308,929, filed September 12, 1963 (now patent No. 3,198,146), which in turn was a continuation of my application Serial No. 144,482, filed October 11, 1961, and which latter is now abandoned.

The invention relates to traveling grates for incinerators and the like, and more particularly to the construction of the flexible grate or apron which moves over a suitable structural support within the incinerator or furnace and actually transports the combustible material while it is being burned. Specifically, the present invention relates to the construction and mounting of links which, when articulated together, form an endless chain which is a component of the flexible grate or apron above referred to.

In my parent applications aforesaid, there is disclosed a traveling grate construction in which several endless chains are mounted to travel in horizontally spaced parallel relationship. These endless chains are composed of articulated links which constitute not only drive links, but also grate links. That is to say, such links serve not only the function of transmitting forces which drive the traveling grate about its orbit, but also that the same links do themselves support material which is undergoing combustion. As disclosed in said applications, however, such combination drive and grate links serve a third function, namely, that of supporting the ends of grate bars, which grate bars extend between two such endless chains, and have one of their ends attached to a grate link in one chain, while the other end is attached to a grate link in another chain. These grate bars serve to support removable and replaceable members called keys, which themselves constitute (for the lineal extent of the grate bars) the surface upon which the combustible material is sustained while being burned. Thus the combination drive and grate links not only sustain the load of material immediately above them, but also the load of a substantial part of the material above grate bars at one or both sides thereof.

The particular form of the combination drive link and grate link shown in the aforesaid applications has been found to be more shortlived in some sections than in others, and accordingly it is one of the objects of the present invention to provide such links with readily removable and replaceable combustible-sustaining portions; and to provide such removable and replaceable portions in a construction such that such replacement can be accomplished without either de-articulating the chain or disconnecting the grate bars which may be attached to the link at which the replacement is to be made.

Whereas in said parent application, the combination drive and grate links were shown as being equipped with rollers having flanges which maintained the rollers in alignment astride a supporting rail, there are certain operating conditions under which such rollers tend to hang and wear flat, and accordingly it is another object of the invention to equip such combination drive and grate links with bearing members which are not intended to rotate.

Accordingly, the present invention contemplates that combination drive and grate links of the general character disclosed in the aforesaid applications be equipped with nonrotatable, albeit limitedly oscillatable, bearing members for transmitting the load of the traveling grate to the stationary supporting rails along which it moves; and

that the cover part of such drive links be made readily replaceable, preferably without necessitating that the given link be dearticulated from its neighbors or disconnected from the grate bars which it sustains.

Other objects and advantages of the invention will become apparent to those skilled in the art when the following description is read in connection with the accompanying drawings, in which: FIGURE 1 is a worms-eye view of a plurality of combination drive and grate links of the character aforesaid, which are articulated together and equipped with non rotatable bearing members;

FIGURE 2 is a perspective view of a bearing member of the type shown in FIGURE 1;

FIGURE 3 is a perspective view of an alternative form of non-rotatable bearing member suitable for use in lieu of that shown in FIGURE 2, and in lieu of the rollers shown in the applications aforesaid;

FIGURE 4 is a perspective view genearlly comparable to FIGURE 1, but showing the links equipped with removable covers, and with the conventional roller type bearing members;

FIGURE 5 is a perspective view of a single link as shown in FIGURE 4, with the cover removed, and without bearing members or articulating pins;

FIGURE 6 is a perspective view of a removable and replaceable cover for use in connection with the link shown in FIGURE 5;

FIGURE 7 is a sectional view taken generally in plane 77 of FIGURE 4;

FIGURE 8 is a sectional view comparable to that of FIGURE 7, but showing the link equipped with nonrotatable bearing members of the type illustrated in FIG- URE 3, and articulated to other such links fore and aft;

FIGURE 9 is a perspective view illustrating three positions of the removable cover relative to the link, which positions are occupied successively in the process of removing or replacing the removable cover; and

FIGURE 10 is a View corresponding generally to FIG- URE 4 of my aforesaid patent, and showing in section transverse to the direction of movement, a typical organization of parts in a traveling grate of the character comtemplated.

Referring first to FIGURE 10 of the drawings, a traveling grate of the character contemplated is provided with a supporting structure which includes a plurality of rails 1 running in the direction of travel of the grate. The rails 1, of which two are shown in FIGURE 10, but of which there may be many, are spaced apart a distance which, in practice, may be on the order of two to six feet. Each such rail 1 sustains the load of an individual endless chain, typical portions of whichare illustrated in FIGURES 1, 4 and 8 of the drawings. For example, such a chain may be composed of many links, such as 2 (FIGURE 1) or 42 (FIGURE 4), arranged end to end and articulated together by articulating pins 3, which carry bearing members such as skid blocks 4, rollers 44, or skid blocks 74. Between the links 42 on one rail 1 and the links 42 on the adjacent rail 1, there extends a grate bar 5 whose opposite ends are connected, respectively, to the pads 6 (FIGURE 1) or 46 (FIGURES 4, 5 and 79). Upon the grate bars 5, there are removably mounted a plurality of grate keys 7, all as more fully described in my aforesaid patent.

The combination drive and grate links shown in FIG- URE 1 of the drawings are (with one exception later to be pointed out) in a form identical with that disclosed in my aforesaid patent, but the bearing members 4 are nonrotatable and of the form shown in FIGURE 2. The latter are skid blocks provided with depending flanges 8 spaced apart a distance sufficient to enable the flanges to straddle the head of supporting rails such as 1. The skid blocks 4 are each provided with a hole 9 for the reception of articulating pin 3, and are further provided with a slot 10 for the reception of pin 11.

The aforesaid single exception to the identity of links 2 with their counterparts in my aforesaid patent is the provision, in the opposite webs 12 thereof, of a pair of aligned holes 13 for the reception of pins 11..

Thus, when pin 11 occupies slot 10 of a skid block 4 which is mounted upon articulating pin 9, rotation of the skid block about pin 9 as an axis is precluded, but it is preferable that the slot 10 be wider than the diameter of pin 11 so as to permit a limited amplitude of oscillation of block 4 about pin 9 as an axis. Under normal conditions, the amplitude of such operation does t exceed thirty degrees, but in any event, such is sufiicient only to allow the skid block to accommodate itself to changes in the curvature of the supporting rails 1 at one or both ends of a horizontal run.

The restraint imposed by the disposition of pins 11 in the slot 10 of each such skid block assures proper orientation of the skid block with reference to its supporting rail 1 as it approaches engagement therewith.

An alternative form of skid block is shown in FIGURE 3, where the block 34 is substantially identical with the block 4 shown in FIGURE 2, save that it has no depending flanges. The block 34 is, however, equipped with a slot 30 and a hole 39, which are co-related in the same manner as shown and described in connection with the skid block 4.

In FIGURES 4, 5, 7 and 8, the combination drive and grate link is identical with that shown in FIGURE 1, with the exception that the cover portion of the link is in two parts, namely, an integral portion 14 (shown in FIGURE and a removable portion 15 (shown in FIG- URE 6). Referring to FIGURE 5, it will be observed that the integral cover portion 14 of the link 42 is provided with a keyway 16. In the form shown, the keyway 16 is Wider at each end 17 and 18 than at its center 19, but it is sufficient for the purposes of the invention that one or the other of the Wider portions 17 and 18 be omitted, that is to say, left filled with metal.

Referring now to FIGURE 6, it will be observed that the removable cover piece 15 is provided on its underside with a tang 20 and a lip 21. The sidewise dimension of the piece 15 is the same as that of integral portion 14. The fore-aft dimension of the tank 211 is such that it will readily pass through the wider portion 17 or 13 of keyway 16, while the space between tang 20 and the underside of removable cover piece 15 is but slightly greater than the thickness of integral cover 14, as clearly shown in FIGURE 7. Likewise, the distance between lip 21 and the underside of removable cover piece 15 is but slightly in excess of the thickness of integral cover piece 14 at its rearward extremity.

In operative position, the lip 21 of the removable cover piece is engaged over the rearward extremity 2.2 of the integral cover piece 14, as clearly shown in FIG- URES 7 and 8, and by the full lines in FIGURE 9, while the tang 20 is disposed in the constricted portion 19 of keyway 16. Thus, in operative position, the removable cover piece 15 is centered (in the direction parallel to articulating pins 3) in keyway 16 and on the integral cover piece 14, as shown in full lines in FIGURE 9. In order to apply the removable cover piece 15 to the integral cover piece 14, the former is first disposed in the position shown in dot-dash lines in FIGURE 9, where lip 21 underlies extremity 22, and tang 20 is aligned vertically with either wide portion 17 or wide portion 18 of keyway 16. In other words, at the initial step of application the longitudinal center line of removable cover 15 is substantially disaligned from the longitudinal center line of integral cover piece 14. The degree of the disalignment is such as to bring tang 20 into position such that its center line lies in the same vertical plane as the center line of enlarged portion 17 or enlarged portion 18 of keyway 16, or nearly so. When thus aligned, rotation of removable cover 15 about the line of engagement between rear extremity 22 and lip 21 will bring the tang 21 into position within enlarged portion 17 or 18, and further movement thereof will pass the tank through such enlarged portion so that cover member 15 now occupies the position shown in dotted lines in FIGURE 9, at which the longitudinal center line of removable cover 15 is still substantially disaligned with the longitudinal center line of integral cover 14. Then movement of the removable cover 15 transversely (i.e., parallel to the axis of articulating pins 3) until the longitudinal center line thereof is substantially aligned with the longitudinal center line of integral cover 14 will bring the tang 20 into position in the constricted portion 19 of keyway 16, with the end thereof underlying tongue 23 in integral cover 14-. In this position, the removable cover 15 will no longer rock about the extremity 22 of integral cover 14. This is its position in operation.

When in the operative position just described, the removable cover 15 is maintained against transverse movement by the disposition of a grate key such as 24 on one side thereof, and a key such as 25 on the other side thereof. In order to maneuver the cover 15 into and out of operative position, space must be provided at one side or the other by the movement of either key 24 or key 25 in the transverse direction. In the form shown in FIG- URE 8, such transverse movement of key 25 is permitted by the removal of a special type of locking key 26, as described in my patent aforesaid.

From the foregoing description, those skilled in the art should readily understand the construction and operation of the invention, and realize that it accomplishes its objects. In particular, the useful life of the combination grate link and drive link, as shown in FIGURE 5, is substantially greater in many situations than is the useful life of the combination drive link and grate link disclosed in my patent aforesaid. On the other hand, the useful life of the removable cover part 15 or fire-plate of this application is comparable to the useful life of the entire combination grate link and drive link disclosed in said patent. Thus, the advantage lies in extending the longevity of the major portion of the combination drive link and grate link by replacing, from time to time, the fire-plate part thereof which previously subjected the entire casting to short life.

It should be distinctly understood that the invention is not limited to the details of the foregoing disclosure, save as set out in the accompanying claims.

Having thus described the invention, what is claimed and desired to be secured by Letters Patent is:

1. In an endless traveling grate having a plurality of spaced parallel series of drive links, articulating pins connecting each drive link to its leading and trailing neighbors in the same series, said articulating pins extending horizontally normal to the direction of travel of said endless grate, a supporting rail for each series of articulated drive links, grate bars extending laterally between and interconnecting drive links in different series, and bearing members between said drive links and the sup porting rail for the corresponding series of drive links, said bearing members being mounted upon said articulating pins, said drive links comprising an integral casting including a cover part and a pair of drive bars depending from said cover part, said bearing members consisting of skid blocks, and means for limiting the rotation of said skid blocks about said articulating pins.

2. In an endless traveling grate having a plurality of spaced parallel series of drive links, articulating pins connecting each drive link to its leading and trailing neighbors in the same series, said articulating pins extending horizontaly normal to the direction of travel of said endless grate, a supporting rail for each series of articulated drive links, grate bars extending laterally between and interconnecting drive links in different series, and bearing members between said drive links and the supporting rail for the corresponding series of drive links, said bearing members being mounted upon said articulating pins, said drive links comprising an integral casting including a cover part and a pair of drive bars depending from said cover part, and means for limiting rotation of said articulating pins relative to said drive links.

3. In an endless traveling grate having a plurality of spaced parallel series of drive links, articulating pins connecting each drive link to its leading and trailing neighbors in the same series, said articulating pins extending horizontally normal to the direction of travel of said endless grate, a supporting rail for each series of articulated drive links, grate bars extending laterally between and interconnecting drive links in different series, and bearing members between said drive links and the supporting rail for the corresponding series of drive links, said bearing members being mounted upon said articulating pins, said drive links comprising an integral casting including a cover part and a pair of drive bars depending from said cover part, said cover part overhanging the leading end of its associated pair of drive bars, and a fire-plate removably mounted on said cover part and projecting in the trailing direction from the cover part for a distance sufiicient to overhang a substantial leading portion of the cover part of the next succeeding drive link in the same series.

4. In an endless traveling grate, a combined drive and grate link comprising,

(a) a cover part having an integral pair of spaced drive bars depending therefrom and projecting therebehind, said cover part overlapping the forward ends of said drive bars, and

(b) a readily separable fire'plate interlocked with said cover part and extending for a substantial distance over the portions of said drive bars which project behind said cover part.

5. In an endless traveling grate, a combined drive and grate link comprising,

(a) a cover part having a pair of spaced drive bars depending therefrom and projecting therebehind, and

(b) a readily separable fire-plate interlocked with said cover part and extending over the projecting portions of said drive bars,

said interlock between the cover part and the fire-plate comprising an L-shaped keyway in one of said parts and an L-shaped key in another of said parts; said keyway having one leg extending substantially parallel with said drive bars, and the other leg extending in the horizontally transverse direction; said key having one leg extending substantially parallel with said drive bars, and the other leg extending in the vertically transverse direction; and said key and keyway being so disposed that when the center line of said fire-plate is vertically aligned with the center line between said drive bars, said one leg of said key is disaligned, in the direction substantially parallel with said drive bars, with said one leg of said keyway.

6. The link of claim 5 wherein said fire-plate has a lip underlying the end of said cover part.

7. A stoker link comprising a body, a tire-plate, :and means connecting said fire-plate to said body to transmit motion from the latter to the former in one direction when said body and fire-plate are in operative alignment in said direction, and means operative only when said body and fire-plate are out of operative alignment in said direction to release said connecting means.

8. The combination of claim 3 wherein said drive bars which depend from said cover part project therebehind, and the fire-plate is interlocked with the cover part and extends over the projecting portion of said drive bars.

9. The combination of claim 8 wherein the interlock between the cover part and the fire-plate comprises an L-shaped keyway in one of said parts and an L-shaped key in another of said parts; said keyway having one leg extending substantially parallel with said drive bars, and the other leg extending in the horizontally transverse direction; said key having one leg extending substantially parallel with said drive bars, and the other leg extending in the vertically transverse direction; and said key and keyway being so disposed that when the center line of said fire-plate is vertically aligned with the center line between said drive bars, said one leg of said key is disaligned, in the direction substantially parallel with said drive bars, with said one leg of said keyway.

10. The combination of claim 9 wherein said fire-plate has a lip underlying the end of said cover part.

11. The combination of claim 3 having means for connecting said fire-plate to said integral casting to transmit motion from the latter to the former in one direction When said integral casting and fire-plate are in operative alignment in said direction, and means operative only when said integral casting and fire-plate are out of operative alignment to release said connecting means.

References Cited by the Examiner UNITED STATES PATENTS 520,986 6/ 1894 Gulickson -40 1,619,842 3/1927 Wright 126168 1,670,642 5/1928 Van Brunt 110-40 1,700,707 1/1929 Peck 1lO40 1,756,020 4/1930 Duncan 11040 2,725,021 11/ 1955 Kessler 110-40 2,804,834 9/1957 Rivers 11040 FOREIGN PATENTS 275,428 8/ 1927 Great Britain.

KENNETH W. SPRAGUE, Primary Examiner. 

1. IN AN ENDLESS TRAVELING GRATE HAVING A PLURALITY OF SPACED PARALLEL SERIES OF DRIVE LINKS, ARTICULATING PINS CONNECTING EACH DRIVE LINK TO ITS LEADING AND TRAILING NEIGHBORS IN THE SAME SERIES, SAID ARTICULATING PINS EXTENDING HORIZONTALLY NORMAL TO THE DIRECTION OF TRAVEL OF SAID ENDLESS GRATE, A SUPPORTING RAIL FOR EACH SERIES OF ARTICLATED DRIVE LINKS, GRATE BARS EXTENDING LATERALLY BETWEEN AND INTERCONNECTING DRIVE LINKS IN DIFFERENT SERIES, AND BEARING MEMBERS BETWEEN SAID DRIVE LINKS AND THE SUPPORTING RAIL FOR THE CORRESPONDING SERIES OF DRIVE LINKS, SAID BEARING MEMBERS BEING MOUNTED UPON SAID ARTICULATING PINS, SAID DRIVE LINKS COMPRISING AN INTEGRAL CASTING INCLUDING A COVER PART AND A PAIR OF DRIVE BARS DEPENDING FROM SAID COVER PART, SAID BEARING MEMBERS CONSISTING OF SKID BLOCKS, AND MEANS FOR LIMITING THE ROTATION OF SAID SKID BLOCKS ABOUT SAID ARTICULATING PINS. 